Yount, 1954
In both solitary and aggregate zooids: test generally soft, smooth, and lacking any echinae or projections.
Solitary zooids
Oral and atrial openings terminal (Cyclosalpa pinnata). Seven body muscles symmetrically arranged. Intestine beside the gill anterior, united with it over most of its length. Pairs of light organs generally present, arranged laterally between or on the body muscles.
Aggregate zooids
Oral opening terminal, atrial opening dorsal or terminal (Cyclosalpa pinnata 1). Four body muscles. Gut forming either an extended tube or loose loop; never forming a compact nucleus. Intestinal caecum and a blood-forming organ can be present. Ovary and embryo between MIII and MIV, on the right side. Testis between endostyle and gut, or protruding posteriorly beyond the gut. Aggregate zooids attached by a single peduncle.
Genera treated:
Genus Cyclosalpa de Blainville, 1827
Genus Helicosalpa Todaro, 1902